

_CLIGHT = LIGHT_SPEED = 299792458.0 # speed of light [unit: m/s]

_OMEGAe_GPS = 7.2921151467e-05 # angular rotation of Earth [unit:rad/s]
_U_GPS=Earth_s_Gravitational_Constant=3.986005e14 # WGS-84坐标系中的地球引力常数

_OMEGAe_BDS = 7.292115e-05 
_U_BDS = 3.986004418e14

_LEAP_SECONDS = 18 # 闰秒

'''
WGS-84 椭球参数
'''
_WGS84_a = 6378137.0 # 长半轴(m)
_WGS84_b = 6356752.31424517 # 短半轴(m)
_WGS84_f = 1/298.257223563 # 扁率

'''
CGCS2000
'''
_CGCS2000_a = 6378137.0 # 长半轴(m)
_CGCS2000_b = 6356752.31414 # 短半轴(m)
_CGCS2000_f = 1/298.257222101 # 扁率
'''
GPS
'''
_MAXDTOE = 7200 # max time difference to GPS Toe (s)

'''
system
'''
_SYS_GPS=1
_SYS_BDS=2
_SYS_UNKNOWN=0
